Lunch box



FIG. 1 is a front elevation of the inventive design;

FIG. 2 is a top plan view of the design;

FIG. 3 is a rear elevational view of the design;

FIG. 4 is a bottom plan view of the design;

FIG. 5 is a side elevation of the design taken from the right of FIG. 1,it being understood that the opposite side is a mirror image of FIG. 5;and,

FIG. 6 is a perspective view of the design from above and the right sideof FIG. 1.

The ornamental design for a lunch box, as shown and described.